The royal family sang along, waved their arms and shared laughs as they enjoyed a night out at the Platinum Party at the Palace.
Princess Charlotte and Prince George sat in front row of the royal box between their parents, clapping along to Queen + Adam Lambert’s performance of Don’t Stop Me Now, as the youngsters stayed up late to make a surprise appearance.
The Windsors – as many as 40 of them out in force – joined in whole-heartedly with the chorus during Sir Rod Stewart’s rendition of the hit anthem Sweet Caroline as the words were projected onto the screen, with eight-year-old George belting out a “bom, bom, bom” perfectly in time.
The Duchess of Cornwall enthusiastically waved her union flag up high, as the Prince of Wales moved his decisively to the beat.
Charlotte was at one point seen reading a programme and tapping her mother on the elbow, while at times Kate bopped up and down to the music.
The duchess burst out laughing when comedian Lee Mack tried to get the royal box to join in with his delivery of the late Queen frontman Freddie Mercury’s “Ay-Oh” chant.
During Elbow’s appearance, Charlotte, in a sequinned red dress with matching red cardigan and with her hair down, peered forward to look at the stage.
Zara and Mike Tindall chatted with their heads close together during the show, as ex-rugby player Mike waved his union flag.
At one point George slumped down in his chair, leaning towards his father during the two-and-a-half hour run of performance, set on three stages in front of Buckingham Palace on the third day of the Jubilee bank holiday weekend.
For Jason Donovan’s rendition of Any Dream Will Do from Joseph And The Amazing Technicolor Dreamcoat, Camilla moved her arms up high from side to side, as Charles did too before pausing to adjust his illuminated wristband.
The Cambridges also waved their flags, with William singing along with the words: “May I return…to the beginning.”
Sam Ryder, in a sequined union flag jumpsuit, performed his Eurovision hit Space Man and impressed Anne, who clapped afterwards, while Charles appeared to enjoy Andrea Bocelli’s singing.
Also in the royal box were Prime Minister Boris Johnson and his wife Carrie, as well as Labour leader Sir Keir Starmer.
The royals stood for the national anthem, having listened as Charles took to the stage, with Camilla at his side, to pay tribute to the Queen.
Late in the evening, Kate was seen whispering to her daughter, as Charlotte snuggled up to her mother.
As the night progressed, the princess put on a red cape to keep her warm in the night air.
There was a patriotic display from the Cambridges, with Kate in white, Charlotte in red, and William and George in blue outfits.
Princess Beatrice and husband Edoardo Mapelli Mozzi were pictured waving to someone they recognised as they took their seats with Princess Eugenie and Jack Brooksbank.
Others royals who turned out for the musical extravaganza included the Wessex family and a number of the Queen’s cousins – but the Duke and Duchess of Sussex were missing, spending the day – their daughter Lilibet’s first birthday – privately.